brain-hackers_pepepper-mirror
/
linux-brain
mirror of https://github.com/brain-hackers/linux-brain.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

ACPI: platform: Unregister stale platform devices 

[ Upstream commit cb0701acfa7e3fe9e919cf2aa2aa939b7fd603c2 ]

When commit 68bdb67732 ("ACPI: add support for ACPI reconfiguration
notifiers") introduced reconfiguration notifiers, it missed the point
that the ACPI table, which might be loaded and then unloaded via
ConfigFS, could contain devices that were not enumerated by their
parents.

In such cases, the stale platform device is dangling in the system
while the rest of the devices from the same table are already gone.

Introduce acpi_platform_device_remove_notify() notifier that, in
similar way to I²C or SPI buses, unregisters the platform devices
on table removal event.

Fixes: 68bdb67732 ("ACPI: add support for ACPI reconfiguration notifiers")
Depends-on: 00500147cb ("drivers: Introduce device lookup variants by ACPI_COMPANION device")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[ rjw: Changelog & function rename ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Andy Shevchenko 2019-08-30 17:34:32 +03:00 committed by Greg Kroah-Hartman
parent c99f4a8c66
commit aff509a3a1
2 changed files with 44 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

43
drivers/acpi/acpi_platform.c
View File

@ -31,6 +31,44 @@ static const struct acpi_device_id forbidden_id_list[] = {
{"", 0},
};
static struct platform_device *acpi_platform_device_find_by_companion(struct acpi_device *adev)
{
struct device *dev;
dev = bus_find_device_by_acpi_dev(&platform_bus_type, adev);
return dev ? to_platform_device(dev) : NULL;
}
static int acpi_platform_device_remove_notify(struct notifier_block *nb,
unsigned long value, void *arg)
{
struct acpi_device *adev = arg;
struct platform_device *pdev;
switch (value) {
case ACPI_RECONFIG_DEVICE_ADD:
/* Nothing to do here */
break;
case ACPI_RECONFIG_DEVICE_REMOVE:
if (!acpi_device_enumerated(adev))
break;
pdev = acpi_platform_device_find_by_companion(adev);
if (!pdev)
break;
platform_device_unregister(pdev);
put_device(&pdev->dev);
break;
}
return NOTIFY_OK;
}
static struct notifier_block acpi_platform_notifier = {
.notifier_call = acpi_platform_device_remove_notify,
};
static void acpi_platform_fill_resource(struct acpi_device *adev,
const struct resource *src, struct resource *dest)
{
@ -130,3 +168,8 @@ struct platform_device *acpi_create_platform_device(struct acpi_device *adev,
return pdev;
}
EXPORT_SYMBOL_GPL(acpi_create_platform_device);
void __init acpi_platform_init(void)
{
acpi_reconfig_notifier_register(&acpi_platform_notifier);
}

1
drivers/acpi/scan.c
View File

@ -2174,6 +2174,7 @@ int __init acpi_scan_init(void)
acpi_pci_root_init();
acpi_pci_link_init();
acpi_processor_init();
acpi_platform_init();
acpi_lpss_init();
acpi_apd_init();
acpi_cmos_rtc_init();